程序包 cn.taketoday.lang

类 Assert

java.lang.Object
cn.taketoday.lang.Assert
public abstract class Assert extends Object
Assertion utility class that assists in validating arguments.

Useful for identifying programmer errors early and clearly at runtime.

For example, if the contract of a public method states it does not allow null arguments, Assert can be used to validate that contract. Doing this clearly indicates a contract violation when it occurs and protects the class's invariants.

Typically used to validate method arguments rather than configuration properties, to check for cases that are usually programmer errors rather than configuration errors. In contrast to configuration initialization code, there is usually no point in falling back to defaults in such methods.

This class is similar to JUnit's assertion library. If an argument value is deemed invalid, an IllegalArgumentException is thrown (typically). For example: 

 Assert.notNull(clazz, "The class is required");
 Assert.isTrue(i > 0, "The value must be greater than zero");

Mainly for internal use within the framework; consider Apache's Commons Lang for a more comprehensive suite of String utilities.

从以下版本开始:
2.1.7
作者:
Keith Donald, Juergen Hoeller, Sam Brannen, Colin Sampaleanu, Rob Harrop, TODAY
2020-01-31 17:16

  • 构造器概要

    构造器
    构造器
    说明
    Assert()
     

  • 方法概要

    修饰符和类型
    方法
    说明
    private static void
    assignableCheckFailed(Class<?> superType, Class<?> subType, String msg)
     
    static void
    doesNotContain(String textToSearch, String substring)
    Assert that the given text does not contain the given substring.
    static void
    doesNotContain(String textToSearch, String substring, String message)
    Assert that the given text does not contain the given substring.
    static void
    doesNotContain(String textToSearch, String substring, Supplier<String> messageSupplier)
    Assert that the given text does not contain the given substring.
    private static boolean
    endsWithSeparator(String msg)
     
    static void
    hasLength(String text)
    Assert that the given String is not empty; that is, it must not be null and not the empty String.
    static void
    hasLength(String text, String message)
    Assert that the given String is not empty; that is, it must not be null and not the empty String.
    static void
    hasLength(String text, Supplier<String> messageSupplier)
    Assert that the given String is not empty; that is, it must not be null and not the empty String.
    static void
    hasText(String text)
    Assert that the given String contains valid text content; that is, it must not be null and must contain at least one non-whitespace character.
    static void
    hasText(String text, String message)
    Assert that the given String contains valid text content; that is, it must not be null and must contain at least one non-whitespace character.
    static void
    hasText(String text, Supplier<String> messageSupplier)
    Assert that the given String contains valid text content; that is, it must not be null and must contain at least one non-whitespace character.
    private static void
    instanceCheckFailed(Class<?> type, Object obj, String msg)
     
    static void
    isAssignable(Class<?> superType, Class<?> subType)
    Assert that superType.isAssignableFrom(subType) is true.
    static void
    isAssignable(Class<?> superType, Class<?> subType, String message)
    Assert that superType.isAssignableFrom(subType) is true.
    static void
    isAssignable(Class<?> superType, Class<?> subType, Supplier<String> messageSupplier)
    Assert that superType.isAssignableFrom(subType) is true.
    static void
    isInstanceOf(Class<?> type, Object obj)
    Assert that the provided object is an instance of the provided class.
    static void
    isInstanceOf(Class<?> type, Object obj, String message)
    Assert that the provided object is an instance of the provided class.
    static void
    isInstanceOf(Class<?> type, Object obj, Supplier<String> messageSupplier)
    Assert that the provided object is an instance of the provided class.
    static void
    isNull(Object object)
    Assert that an object is null.
    static void
    isNull(Object object, String message)
    Assert that an object is null.
    static void
    isNull(Object object, Supplier<String> messageSupplier)
    Assert that an object is null.
    static void
    isTrue(boolean expression)
    Assert a boolean expression, throwing an IllegalArgumentException if the expression evaluates to false.
    static void
    isTrue(boolean expression, String message)
    Assert a boolean expression, throwing an IllegalArgumentException if the expression evaluates to false.
    static void
    isTrue(boolean expression, Supplier<String> messageSupplier)
    Assert a boolean expression, throwing an IllegalArgumentException if the expression evaluates to false.
    private static String
    messageWithTypeName(String msg, Object typeName)
     
    static void
    noNullElements(Object[] array)
    Assert that an array contains no null elements.
    static void
    noNullElements(Object[] array, String message)
    Assert that an array contains no null elements.
    static void
    noNullElements(Object[] array, Supplier<String> messageSupplier)
    Assert that an array contains no null elements.
    static void
    noNullElements(Collection<?> collection, String message)
    Assert that a collection contains no null elements.
    static void
    noNullElements(Collection<?> collection, Supplier<String> messageSupplier)
    Assert that a collection contains no null elements.
    static void
    notEmpty(Object[] array)
    Assert that an array contains elements; that is, it must not be null and must contain at least one element.
    static void
    notEmpty(Object[] array, String message)
    Assert that an array contains elements; that is, it must not be null and must contain at least one element.
    static void
    notEmpty(Object[] array, Supplier<String> messageSupplier)
    Assert that an array contains elements; that is, it must not be null and must contain at least one element.
    static void
    notEmpty(Collection<?> collection)
    Assert that a collection contains elements; that is, it must not be null and must contain at least one element.
    static void
    notEmpty(Collection<?> collection, String message)
    Assert that a collection contains elements; that is, it must not be null and must contain at least one element.
    static void
    notEmpty(Collection<?> collection, Supplier<String> messageSupplier)
    Assert that a collection contains elements; that is, it must not be null and must contain at least one element.
    static void
    notEmpty(Map<?,?> map)
    Assert that a Map contains entries; that is, it must not be null and must contain at least one entry.
    static void
    notEmpty(Map<?,?> map, String message)
    Assert that a Map contains entries; that is, it must not be null and must contain at least one entry.
    static void
    notEmpty(Map<?,?> map, Supplier<String> messageSupplier)
    Assert that a Map contains entries; that is, it must not be null and must contain at least one entry.
    static void
    notNull(Object object)
    Assert that an object is not null.
    static void
    notNull(Object object, String message)
    Assert that an object is not null.
    static void
    notNull(Object object, Supplier<String> messageSupplier)
    Assert that an object is not null.
    private static String
    nullSafeGet(Supplier<String> messageSupplier)
     
    static void
    state(boolean expression)
    Assert a boolean expression, throwing an IllegalStateException if the expression evaluates to false.
    static void
    state(boolean expression, String message)
    Assert a boolean expression, throwing an IllegalStateException if the expression evaluates to false.
    static void
    state(boolean expression, Supplier<String> messageSupplier)
    Assert a boolean expression, throwing an IllegalStateException if the expression evaluates to false.

    从类继承的方法 java.lang.Object

    clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

  • 构造器详细资料

    • Assert

      public Assert()

  • 方法详细资料

    • state

      public static void state(boolean expression, String message)
      Assert a boolean expression, throwing an IllegalStateException if the expression evaluates to false.

      Call isTrue(boolean, java.lang.String) if you wish to throw an IllegalArgumentException on an assertion failure. 

      Assert.state(id == null, "The id property must not already be initialized");
      参数:
      expression - a boolean expression
      message - the exception message to use if the assertion fails
      抛出:
      IllegalStateException - if expression is false

    • state

      public static void state(boolean expression, Supplier<String> messageSupplier)
      Assert a boolean expression, throwing an IllegalStateException if the expression evaluates to false.

      Call isTrue(boolean, java.lang.String) if you wish to throw an IllegalArgumentException on an assertion failure. 

       Assert.state(id == null,
              () -> "ID for " + entity.getName() + " must not already be initialized");
      参数:
      expression - a boolean expression
      messageSupplier - a supplier for the exception message to use if the assertion fails
      抛出:
      IllegalStateException - if expression is false

    • state

      public static void state(boolean expression)
      Assert a boolean expression, throwing an IllegalStateException if the expression evaluates to false.

    • isTrue

      public static void isTrue(boolean expression, String message)
      Assert a boolean expression, throwing an IllegalArgumentException if the expression evaluates to false. 
      Assert.isTrue(i > 0, "The value must be greater than zero");
      参数:
      expression - a boolean expression
      message - the exception message to use if the assertion fails
      抛出:
      IllegalArgumentException - if expression is false

    • isTrue

      public static void isTrue(boolean expression, Supplier<String> messageSupplier)
      Assert a boolean expression, throwing an IllegalArgumentException if the expression evaluates to false. 
       Assert.isTrue(i > 0, () -> "The value '" + i + "' must be greater than zero");
      参数:
      expression - a boolean expression
      messageSupplier - a supplier for the exception message to use if the assertion fails
      抛出:
      IllegalArgumentException - if expression is false

    • isTrue

      public static void isTrue(boolean expression)
      Assert a boolean expression, throwing an IllegalArgumentException if the expression evaluates to false.

    • isNull

      public static void isNull(Object object, String message)
      Assert that an object is null. 
      Assert.isNull(value, "The value must be null");
      参数:
      object - the object to check
      message - the exception message to use if the assertion fails
      抛出:
      IllegalArgumentException - if the object is not null

    • isNull

      public static void isNull(Object object, Supplier<String> messageSupplier)
      Assert that an object is null. 
       Assert.isNull(value, () -> "The value '" + value + "' must be null");
      参数:
      object - the object to check
      messageSupplier - a supplier for the exception message to use if the assertion fails
      抛出:
      IllegalArgumentException - if the object is not null

    • isNull

      public static void isNull(Object object)
      Assert that an object is null.

    • notNull

      public static void notNull(Object object, String message)
      Assert that an object is not null. 
      Assert.notNull(clazz, "The class is required");
      参数:
      object - the object to check
      message - the exception message to use if the assertion fails
      抛出:
      IllegalArgumentException - if the object is null

    • notNull

      public static void notNull(Object object, Supplier<String> messageSupplier)
      Assert that an object is not null. 
       Assert.notNull(clazz, () -> "The class '" + clazz.getName() + "' is required");
      参数:
      object - the object to check
      messageSupplier - a supplier for the exception message to use if the assertion fails
      抛出:
      IllegalArgumentException - if the object is null

    • notNull

      public static void notNull(Object object)
      Assert that an object is not null.

    • hasLength

      public static void hasLength(String text, String message)
      Assert that the given String is not empty; that is, it must not be null and not the empty String. 
      Assert.isNotEmpty(name, "Name must not be empty");
      参数:
      text - the String to check
      message - the exception message to use if the assertion fails
      抛出:
      IllegalArgumentException - if the text is empty
      另请参阅:

    • hasLength

      public static void hasLength(String text, Supplier<String> messageSupplier)
      Assert that the given String is not empty; that is, it must not be null and not the empty String. 
       Assert.isNotEmpty(name, () -> "Name for account '" + account.getId() + "' must not be empty");
      参数:
      text - the String to check
      messageSupplier - a supplier for the exception message to use if the assertion fails
      抛出:
      IllegalArgumentException - if the text is empty
      另请参阅:

    • hasLength

      public static void hasLength(String text)
      Assert that the given String is not empty; that is, it must not be null and not the empty String.

    • hasText

      public static void hasText(String text, String message)
      Assert that the given String contains valid text content; that is, it must not be null and must contain at least one non-whitespace character. 
      Assert.hasText(name, "'name' must not be empty");
      参数:
      text - the String to check
      message - the exception message to use if the assertion fails
      抛出:
      IllegalArgumentException - if the text does not contain valid text content
      另请参阅:

    • hasText

      public static void hasText(String text, Supplier<String> messageSupplier)
      Assert that the given String contains valid text content; that is, it must not be null and must contain at least one non-whitespace character. 
       Assert.hasText(name, () -> "Name for account '" + account.getId() + "' must not be empty");
      参数:
      text - the String to check
      messageSupplier - a supplier for the exception message to use if the assertion fails
      抛出:
      IllegalArgumentException - if the text does not contain valid text content
      另请参阅:

    • hasText

      public static void hasText(String text)
      Assert that the given String contains valid text content; that is, it must not be null and must contain at least one non-whitespace character.

    • doesNotContain

      public static void doesNotContain(String textToSearch, String substring, String message)
      Assert that the given text does not contain the given substring. 
      Assert.doesNotContain(name, "rod", "Name must not contain 'rod'");
      参数:
      textToSearch - the text to search
      substring - the substring to find within the text
      message - the exception message to use if the assertion fails
      抛出:
      IllegalArgumentException - if the text contains the substring

    • doesNotContain

      public static void doesNotContain(String textToSearch, String substring, Supplier<String> messageSupplier)
      Assert that the given text does not contain the given substring. 
       Assert.doesNotContain(name, forbidden, () -> "Name must not contain '" + forbidden + "'");
      参数:
      textToSearch - the text to search
      substring - the substring to find within the text
      messageSupplier - a supplier for the exception message to use if the assertion fails
      抛出:
      IllegalArgumentException - if the text contains the substring

    • doesNotContain

      public static void doesNotContain(String textToSearch, String substring)
      Assert that the given text does not contain the given substring.

    • notEmpty

      public static void notEmpty(Object[] array, String message)
      Assert that an array contains elements; that is, it must not be null and must contain at least one element. 
      Assert.notEmpty(array, "The array must contain elements");
      参数:
      array - the array to check
      message - the exception message to use if the assertion fails
      抛出:
      IllegalArgumentException - if the object array is null or contains no elements

    • notEmpty

      public static void notEmpty(Object[] array, Supplier<String> messageSupplier)
      Assert that an array contains elements; that is, it must not be null and must contain at least one element. 
       Assert.notEmpty(array, () -> "The " + arrayType + " array must contain elements");
      参数:
      array - the array to check
      messageSupplier - a supplier for the exception message to use if the assertion fails
      抛出:
      IllegalArgumentException - if the object array is null or contains no elements

    • notEmpty

      public static void notEmpty(Object[] array)
      Assert that an array contains elements; that is, it must not be null and must contain at least one element.

    • noNullElements

      public static void noNullElements(Object[] array, String message)
      Assert that an array contains no null elements.

      Note: Does not complain if the array is empty! 

      Assert.noNullElements(array, "The array must contain non-null elements");
      参数:
      array - the array to check
      message - the exception message to use if the assertion fails
      抛出:
      IllegalArgumentException - if the object array contains a null element

    • noNullElements

      public static void noNullElements(Object[] array, Supplier<String> messageSupplier)
      Assert that an array contains no null elements.

      Note: Does not complain if the array is empty! 

       Assert.noNullElements(array, () -> "The " + arrayType + " array must contain non-null elements");
      参数:
      array - the array to check
      messageSupplier - a supplier for the exception message to use if the assertion fails
      抛出:
      IllegalArgumentException - if the object array contains a null element

    • noNullElements

      public static void noNullElements(Object[] array)
      Assert that an array contains no null elements.

    • notEmpty

      public static void notEmpty(Collection<?> collection, String message)
      Assert that a collection contains elements; that is, it must not be null and must contain at least one element. 
      Assert.notEmpty(collection, "Collection must contain elements");
      参数:
      collection - the collection to check
      message - the exception message to use if the assertion fails
      抛出:
      IllegalArgumentException - if the collection is null or contains no elements

    • notEmpty

      public static void notEmpty(Collection<?> collection, Supplier<String> messageSupplier)
      Assert that a collection contains elements; that is, it must not be null and must contain at least one element. 
       Assert.notEmpty(collection, () -> "The " + collectionType + " collection must contain elements");
      参数:
      collection - the collection to check
      messageSupplier - a supplier for the exception message to use if the assertion fails
      抛出:
      IllegalArgumentException - if the collection is null or contains no elements

    • notEmpty

      public static void notEmpty(Collection<?> collection)
      Assert that a collection contains elements; that is, it must not be null and must contain at least one element.

    • noNullElements

      public static void noNullElements(Collection<?> collection, String message)
      Assert that a collection contains no null elements.

      Note: Does not complain if the collection is empty! 

      Assert.noNullElements(collection, "Collection must contain non-null elements");
      参数:
      collection - the collection to check
      message - the exception message to use if the assertion fails
      抛出:
      IllegalArgumentException - if the collection contains a null element

    • noNullElements

      public static void noNullElements(Collection<?> collection, Supplier<String> messageSupplier)
      Assert that a collection contains no null elements.

      Note: Does not complain if the collection is empty! 

       Assert.noNullElements(collection, () -> "Collection " + collectionName + " must contain non-null elements");
      参数:
      collection - the collection to check
      messageSupplier - a supplier for the exception message to use if the assertion fails
      抛出:
      IllegalArgumentException - if the collection contains a null element

    • notEmpty

      public static void notEmpty(Map<?,?> map, String message)
      Assert that a Map contains entries; that is, it must not be null and must contain at least one entry. 
      Assert.notEmpty(map, "Map must contain entries");
      参数:
      map - the map to check
      message - the exception message to use if the assertion fails
      抛出:
      IllegalArgumentException - if the map is null or contains no entries

    • notEmpty

      public static void notEmpty(Map<?,?> map, Supplier<String> messageSupplier)
      Assert that a Map contains entries; that is, it must not be null and must contain at least one entry. 
       Assert.notEmpty(map, () -> "The " + mapType + " map must contain entries");
      参数:
      map - the map to check
      messageSupplier - a supplier for the exception message to use if the assertion fails
      抛出:
      IllegalArgumentException - if the map is null or contains no entries

    • notEmpty

      public static void notEmpty(Map<?,?> map)
      Assert that a Map contains entries; that is, it must not be null and must contain at least one entry.

    • isInstanceOf

      public static void isInstanceOf(Class<?> type, Object obj, String message)
      Assert that the provided object is an instance of the provided class. 
      Assert.instanceOf(Foo.class, foo, "Foo expected");
      参数:
      type - the type to check against
      obj - the object to check
      message - a message which will be prepended to provide further context. If it is empty or ends in ":" or ";" or "," or ".", a full exception message will be appended. If it ends in a space, the name of the offending object's type will be appended. In any other case, a ":" with a space and the name of the offending object's type will be appended.
      抛出:
      IllegalArgumentException - if the object is not an instance of type

    • isInstanceOf

      public static void isInstanceOf(Class<?> type, Object obj, Supplier<String> messageSupplier)
      Assert that the provided object is an instance of the provided class. 
       Assert.instanceOf(Foo.class, foo, () -> "Processing " + Foo.class.getSimpleName() + ":");
      参数:
      type - the type to check against
      obj - the object to check
      messageSupplier - a supplier for the exception message to use if the assertion fails. See isInstanceOf(Class, Object, String) for details.
      抛出:
      IllegalArgumentException - if the object is not an instance of type

    • isInstanceOf

      public static void isInstanceOf(Class<?> type, Object obj)
      Assert that the provided object is an instance of the provided class. 
      Assert.instanceOf(Foo.class, foo);
      参数:
      type - the type to check against
      obj - the object to check
      抛出:
      IllegalArgumentException - if the object is not an instance of type

    • isAssignable

      public static void isAssignable(Class<?> superType, Class<?> subType, String message)
      Assert that superType.isAssignableFrom(subType) is true. 
      Assert.isAssignable(Number.class, myClass, "Number expected");
      参数:
      superType - the super type to check against
      subType - the sub type to check
      message - a message which will be prepended to provide further context. If it is empty or ends in ":" or ";" or "," or ".", a full exception message will be appended. If it ends in a space, the name of the offending sub type will be appended. In any other case, a ":" with a space and the name of the offending sub type will be appended.
      抛出:
      IllegalArgumentException - if the classes are not assignable

    • isAssignable

      public static void isAssignable(Class<?> superType, Class<?> subType, Supplier<String> messageSupplier)
      Assert that superType.isAssignableFrom(subType) is true. 
       Assert.isAssignable(Number.class, myClass, () -> "Processing " + myAttributeName + ":");
      参数:
      superType - the super type to check against
      subType - the sub type to check
      messageSupplier - a supplier for the exception message to use if the assertion fails. See isAssignable(Class, Class, String) for details.
      抛出:
      IllegalArgumentException - if the classes are not assignable

    • isAssignable

      public static void isAssignable(Class<?> superType, Class<?> subType)
      Assert that superType.isAssignableFrom(subType) is true. 
      Assert.isAssignable(Number.class, myClass);
      参数:
      superType - the super type to check
      subType - the sub type to check
      抛出:
      IllegalArgumentException - if the classes are not assignable

    • instanceCheckFailed

      private static void instanceCheckFailed(Class<?> type, Object obj, String msg)

    • assignableCheckFailed

      private static void assignableCheckFailed(Class<?> superType, Class<?> subType, String msg)

    • endsWithSeparator

      private static boolean endsWithSeparator(String msg)

    • messageWithTypeName

      private static String messageWithTypeName(String msg, Object typeName)

    • nullSafeGet

      private static String nullSafeGet(Supplier<String> messageSupplier)